The nuclear power industry has growing interest in qualifying powder metallurgy with hot isostatic pressing (PM-HIP) to replace traditional alloy fabrication methods for reactor structural components. But there is little known about the response of PM-HIP alloys to reactor conditions. This study directly compares the response of PM-HIP to forged Ni-base Alloy 625 under neutron irradiation doses ∼0.5–1 displacements per atom (dpa) at temperatures ranging ∼321–385 °C. Post-irradiation examination involves microstructure characterization, ASTM E8 uniaxial tensile testing, and fractography. Up through 1 dpa, PM-HIP Alloy 625 appears more resistant to irradiation-induced cavity nucleation than its forged counterpart, and consequently experiences significantly less hardening. This observed difference in performance can be explained by the higher initial dislocation density of the forged material, which represents an interstitial-biased sink that leaves a vacancy supersaturation to nucleate cavities. These findings show promise for qualification of PM-HIP Alloy 625 for nuclear applications, although higher dose studies are needed to assess the steady-state irradiated microstructure.

核电行业对用热等静压 (PM-HIP) 验证粉末冶金以取代反应堆结构部件的传统合金制造方法越来越感兴趣。但是关于 PM-HIP 合金对反应堆条件的响应知之甚少。本研究直接比较了 PM-HIP 对锻造镍基合金 625 在中子辐照剂量下的响应，每原子位移 (dpa) 为 0.5-1，温度范围为 ∼321-385 °C。辐照后检查包括微观结构表征、ASTM E8 单轴拉伸试验和断口法。通过 1 dpa，PM-HIP 合金 625 似乎比其锻造对应物更能抵抗辐照引起的空腔形核，因此硬化显着减少。这种观察到的性能差异可以通过锻造材料的较高初始位错密度来解释，这代表了间隙偏向槽，留下了空位过饱和以形成成核腔。这些发现表明，PM-HIP 合金 625 有望用于核应用，尽管需要更高剂量的研究来评估稳态辐照微观结构。